pub fn odd_fibnacci_sum(threshold: u32) -> u32 {
    let arr = fibonacci(threshold);
    let mut sum = 0;

    for &num in &arr {
        if num % 2 != 0 {
            sum += num;
        }
    }

    sum
}
pub fn fibonacci(threshold: u32) -> Vec<u32> {
    let mut fib = Vec::new();
    let (mut a, mut b) = (1, 1);

    while a <= threshold {
        fib.push(a);
        let next = a + b;
        a = b;
        b = next;
    }

    fib
}